/Engine/Plugins/FX/Niagara/Source/Niagara/Classes/NiagaraSimCache.h
Reads Niagara Quaternion attributes by name from the cache frame and appends them into the OutValues array. Local space emitters provide data at local rotation unless bLocalSpaceToWorld is true. EmitterName - If left blank will return the system simulation attributes. LocalSpaceToWorld - Caches are always stored in the emitters space, i.e. local or world space. You can set this to false if you want the local Quat rather than the world Quat.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=NiagaraSimCache, Meta=(AdvancedDisplay="bLocalSpaceToWorld")) void ReadQuatAttribute ( [TArray](API\Runtime\Core\Containers\TArray)< FQuat > & OutValues, [FName](API\Runtime\Core\UObject\FName) AttributeName, [FName](API\Runtime\Core\UObject\FName) EmitterName, bool bLocalSpaceToWorld, int FrameIndex ) const